144 PARASITIC AMOEBJE OF MAN. 



studied, and this evidence will now be considered in 

 detail. 



The Pathology of Amoebic Dysentery. It is 

 not my intention to discuss fully the pathology of the 

 form of dysentery due to Entamceba histolytica, but 

 to simply call attention to the characteristic lesions of 

 this condition. It is now well recognized that great 

 epidemics of dysentery occur in which amoebae cannot 

 be demonstrated in the lesions of the disease, and that 

 such epidemics are due to a group of bacteria. This 

 type of the disease is known as bacillary dysentery, 

 and the lesions present differ markedly from those 

 found in amoebic dysentery. In the bacillary type 

 the characteristic lesion is a general superficial ulcera- 

 tion of the mucous membrane of the colon accom- 

 panied by intense congestion, while in the more 

 chronic forms the ulcers may penetrate into the sub- 

 mucosa and a general gangrenous condition of the 

 bowel may result, but to one who has had experience 

 in autopsy work upon this form of dysentery a glance 

 is sufficient to distinguish it from the amoebic type. 

 The lesions of the latter form of dysentery cannot be 

 confused with those found in any other variety, 

 although some authorities have tried to prove that the 

 lesions of amoebic dysentery do not differ markedly 

 from those of the bacillary type. Such statements 

 can only be based upon a very limited experience for 



